"The denial of medical care as a weapon of war is a distinct and chilling reality of the war in Syria," the United Nations Commission of Inquiry monitoring human rights in Syria said in its report, titled "Assault on medical care in Syria."
The report alleged regime forces deny medical assistants to people wounded in opposition-controlled or affiliated areas.
"By rejecting the irrefutable and universally accepted principle that those wounded in hostilities must be treated, the parties to the conflict in Syria are setting a dangerous precedent," the report said.
Pro-government forces attacked hospitals in Aleppo an elsewhere with helicopters, the report said.
"These attacks injured and killed civilians receiving treatment in the hospital and medical personnel, significantly damaged the hospital's infrastructure and substantially reduced its ability to treat patients," the panel said.
The commission called the attack on hospitals and medical staff by regime forces "one of the most insidious trends" in the Syrian civil war.
"Government forces deliberately target medical personnel to gain military advantage by depriving the opposition and those perceived to support them of medical assistance for injuries sustained."